A word of warning, from Richard Kohlmann - “Do not convert any hermetic compressors to 134a unless they are designed for 134a
➥ The new 134a refrigerant is not as efficient as R
➥ KollmannMarine Boat Refrigeration Specialist
The older Danfoss BD 2.5 compressors use Freon R12 refrigerant and mineral refrigerant oil
. Refrigerant 134a was not approved for these compressors because of its inability to mix with mineral oil
and to change the oil to a compatible oil might destroy the insulation
on the motor wiring
There is one blended refrigerant, 409a, that can be used as a
replacement for R12 in BD2.5 compressors, but only in an emergency
in cool climates. Warning, never mix refrigerants and always vacuum out the old before inserting a substitute.
Hermetically sealed compressors that are powered by alternating
110 or 220 volt may be filled with Alkylbenzene oil which is compatible with HCFC component refrigerants. Blended refrigerant 409a is recommended as a replacement for R12 in systems where the compressor
contains alylbenzene oil.
Externally driven compressors, engine
driven or those with large 12/24 volt motors are being converted from Freon R12 to 134a refrigerant. This also includes changing to a compatible Poly Ester conversion oil.
If you have one of these systems, contact the system manufacturer for their correct procedures for making this conversion.